Buffersteg

Buffersteg is a form of digital steganography that hides information within data buffers used by computer systems and networks. Rather than embedding hidden data in files or images, buffersteg exploits the way data is buffered, queued, and transmitted by software, hardware, and communication stacks. The goal is to create a covert channel or to watermark data without altering the visible contents or behavior of the systems involved.

The techniques behind buffersteg typically rely on the characteristics of buffering mechanisms. One common approach is to use timing channels, where the sender modulates the availability or timing of a buffer to encode bits, and the receiver detects the pattern to recover the hidden message. Another approach embeds information in underused or padding regions of a buffer, such as unused bits or slots, in a way that remains compatible with normal operation. Implementations often require access to both the sender and receiver ends and can depend on specific buffering policies in operating systems, network stacks, or media pipelines. Buffersteg can be affected by data compression, encryption, and changes in buffering behavior, which may degrade reliability.

Applications of buffersteg appear mainly in security research, covert-channel studies, and digital watermarking. Its practical use is typically limited by low bandwidth, fragility to buffering and compression, and the potential for detection by side-channel analysis. Defenses include monitoring buffer usage and timing patterns, and applying randomization or strict buffering policies to reduce unintended information leakage.